|Septicemic plague resulting in necrosis|
|Specialty|| Infectious disease |
Septicemic plague is one of the three main forms of plague. It is caused by Yersinia pestis , a gram-negative species of bacterium. Septicemic plague is a life-threatening infection of the blood, most commonly spread by bites from infected fleas.
Plague is an infectious disease caused by the bacterium Yersinia pestis. Symptoms include fever, weakness and headache. Usually this begins one to seven days after exposure. In the bubonic form there is also swelling of lymph nodes, while in the septicemic form tissues may turn black and die, and in the pneumonic form shortness of breath, cough and chest pain may occur.
Yersinia pestis is a gram-negative, nonmotile, rod-shaped coccobacillus bacteria, with no spores. It is a facultative anaerobic organism that can infect humans via the Oriental rat flea. It causes the disease plague, which takes three main forms: pneumonic, septicemic and bubonic plagues. All three forms were responsible for a number of high-mortality epidemics throughout human history, including: the sixth century's Plague of Justinian; the Black Death, which accounted for the death of at least one-third of the European population between 1347 and 1353; and the Third Pandemic, sometimes referred to as the Modern Plague, which began in the late nineteenth century in China and spread by rats on steamboats claiming close to 10,000,000 lives. These plagues likely originated in China and were transmitted west via trade routes. Recent research indicates that the pathogen may have been the cause of what is described as the Neolithic Decline, when European populations declined significantly. This would push the date to much earlier and might be indicative of an origin in Europe rather than Eurasia.
A systemic disease is one that affects a number of organs and tissues, or affects the body as a whole.
Like some other forms of gram-negative sepsis, septicemic plague can cause disseminated intravascular coagulation, and is almost always fatal when untreated. However, it only occurs in a minority of cases of Yersinia infection, so that fewer than 5,000 people a year acquire the disease. It is the rarest of the three plague varieties; the other forms are bubonic and pneumonic plague.
Sepsis is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. Common signs and symptoms include fever, increased heart rate, increased breathing rate, and confusion. There may also be symptoms related to a specific infection, such as a cough with pneumonia, or painful urination with a kidney infection. In the very young, old, and people with a weakened immune system, there may be no symptoms of a specific infection and the body temperature may be low or normal, rather than high. Severe sepsis is sepsis causing poor organ function or insufficient blood flow. Insufficient blood flow may be evident by low blood pressure, high blood lactate, or low urine output. Septic shock is low blood pressure due to sepsis that does not improve after fluid replacement.
Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems moving parts of the body. As clotting factors and platelets are used up, bleeding may occur. This may include blood in the urine, blood in the stool, or bleeding into the skin. Complications may include organ failure.
Bubonic plague is one of three types of plague caused by bacterium Yersinia pestis. One to seven days after exposure to the bacteria, flu-like symptoms develop. These symptoms include fever, headaches, and vomiting. Swollen and painful lymph nodes occur in the area closest to where the bacteria entered the skin. Occasionally, the swollen lymph nodes may break open.
The usual symptoms are:
Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. Certain types may present with a fever or sepsis.
However, septicemic plague may cause death before any symptoms occur. Also, the above symptoms are common to many human illnesses and are not considered diagnostic of any form of plague.
Human Yersinia infections most commonly result from the bite of an infected flea or occasionally an infected mammal, but like most bacterial systemic diseases, the disease may be transmitted through an opening in the skin or by inhaling infectious droplets of moisture from sneezes or coughs. In both cases septicemic plague need not be the result, and in particular, not the initial result, but it occasionally happens that bubonic plague for example leads to infection of the blood, and septicemic plague results. If the bacteria happen to enter the bloodstream rather than the lymph or lungs, they multiply in the blood, causing bacteremia and severe sepsis. In septicemic plague, bacterial endotoxins cause disseminated intravascular coagulation (DIC), where tiny blood clots form throughout the body, commonly resulting in localised ischemic necrosis, tissue death from lack of circulation and perfusion.
Bacteremia is the presence of bacteria in the blood. Blood is normally a sterile environment, so the detection of bacteria in the blood is always abnormal. It is distinct from sepsis, which is the host response to the bacteria.
Necrosis is a form of cell injury which results in the premature death of cells in living tissue by autolysis.
Perfusion is the passage of fluid through the circulatory system or lymphatic system to an organ or a tissue, usually referring to the delivery of blood to a capillary bed in tissue. Perfusion is measured as the rate at which blood is delivered to tissue, or volume of blood per unit time per unit tissue mass. The SI unit is m3/(s·kg), although for human organs perfusion is typically reported in ml/min/g. The word is derived from the French verb "perfuser" meaning to "pour over or through". All animal tissues require an adequate blood supply for health and life. Poor perfusion (malperfusion), that is, ischemia, causes health problems, as seen in cardiovascular disease, including coronary artery disease, cerebrovascular disease, peripheral artery disease, and many other conditions.
DIC results in depletion of the body's clotting resources, so that it can no longer control bleeding. Consequently, the unclotted blood bleeds into the skin and other organs, leading to red or black patchy rash and to hematemesis (vomiting blood) or hemoptysis (spitting blood). The rash may cause bumps on the skin that look somewhat like insect bites, usually red, sometimes white in the center.
Hematemesis is the vomiting of blood. The source is generally the upper gastrointestinal tract, typically above the suspensory muscle of duodenum. Patients can easily confuse it with hemoptysis, although the latter is more common. Hematemesis "is always an important sign".
Hemoptysis is the coughing up of blood or blood-stained mucus from the bronchi, larynx, trachea, or lungs. This can occur with lung cancer, infections such as tuberculosis, bronchitis, or pneumonia, and certain cardiovascular conditions. Hemoptysis is considered massive at 300 mL. In such cases, there are always severe injuries. The primary danger comes from choking, rather than blood loss.
Untreated septicemic plague is almost always fatal. Early treatment with antibiotics reduces the mortality rate to between 4 and 15 percent. Death is almost inevitable if treatment is delayed more than about 24 hours, and some people may even die on the same day they present with the disease.
Septicemic plague is caused by horizontal and direct transmission.Horizontal transmission is the transmitting of a disease from one individual to another regardless of blood relation. Direct transmission occurs from close physical contact with individuals, through common air usage, from direct bite from a flea or an infected rodent. Most common rodents may carry the bacteria and so may Leporidae such as rabbits:
Significant carriers of the bacteria in the United States include:
The bacteria are cosmopolitan, mainly in rodents in all continents except Australia and Antarctica. The greatest frequency of human plague infections occur in Africa. The bacteria most commonly appear in rural areas and wherever there is poor sanitation, overcrowding, and high rodent populations in urban areas. Outdoor activities such as hiking, camping, or hunting where plague-infected animals may be found, increase the risk of contracting septicemic plague, and so do certain occupations such as veterinary or other animal-related work.
A doctor or veterinarian will perform a physical exam which includes asking about the medical history and possible sources of exposure.The following possible test could include:
The following steps and precautions should be used to avoid infection of the septicemic plague:
Starting antibiotics early is a first step in treating septicemic plague in humans. One of the following antibiotics may be used:
Lymph nodes may require draining and the patient will need close monitoring.
In animals, antibiotics such as tetracyline or doxycycline can be used. Intravenous drip may be used to assist in dehydration scenarios. Flea treatment can also be used. In some cases euthanasia may be the best option for treatment and to prevent further spreading.
In 2015, Taylor Gaes, a 16-year-old in Larimer County in northern Colorado, contracted septicemic plague after being bitten by a flea that had bitten a rodent on his family's rural property.Only three people in Colorado contracted the bacteria in the previous thirty years.
Septicemic plague was the least common of the three plague varieties that occurred during the Black Death from 1348 to 1350(the other two being bubonic plague and pneumonic plague). Like the others, septicemic plague spread from the East through trade routes on the Black Sea and down to the Mediterranean Sea.
Major port cities such as Venice and Florence were hit the hardest. The massive loss of working population in Europe following the Black Death, resulting in increased economic bargaining power of the serf labour force, was a major precipitating factor for the Peasants' Revolt of 1381.
Septicemic plague is a zoonosis,a disease that generally is acquired by humans from animals, such as rodents and carnivores. Goats, sheep and camels also may carry the bacteria. Cats rarely develop clinical signs but can be infected. Areas west of the Great Plains of North America are one region where plague-infected animals commonly occur. Plague-infested animals are found in many other countries as well, especially in developing countries where health controls are not effective.
Animals that commonly carry plague bacteria are largely rodents and Leporidae, but carnivores sometimes also become infected by their prey. Prey animals are not immune to the disease, and outbreaks of various strains of plague, such as sylvatic plague, have on occasion devastated populations of black-tailed prairie dogs and black-footed ferrets.
Plague has been active in black-tailed prairie dog populations since the 1960s. In the United States outbreaks only occur in the western States and they are devastating, with mortality rates near 100% because the animals have no immunity to the plague. Survivors are the ones that happened not to become infected and colonies that recover from a plague outbreak remain at risk.
Because black-footed ferrets prey on black-tailed prairie dogs, wild ferret populations also fall victim to sylvatic plague. An outbreak can kill nearly 100% of ferrets in a population, and surviving ferrets commonly face starvation because the prairie dogs are their main prey. Spray-and-vaccinate campaigns have aimed at preventing the spread of the plague among these animals.
Similar septicemic problems occurs in many countries across the world, especially in developing countries where spending on health systems is very low and health controls are not effective.
The Black Death, also known as the Great Plague, the Black Plague, or the Plague, was one of the most devastating pandemics in human history, resulting in the deaths of an estimated 75 to 200 million people in Eurasia and peaking in Europe from 1347 to 1351. The bacterium Yersinia pestis, which results in several forms of plague, is believed to have been the cause. The Black Death was the first major European outbreak of plague, and the second plague pandemic. The plague created a number of religious, social and economic upheavals which had profound effects on the course of European history.
A human pathogen is a pathogen that causes disease in humans.
Pneumonic plague is a severe lung infection caused by the bacterium Yersinia pestis. Symptoms include fever, headache, shortness of breath, chest pain, and cough. They typically start about three to seven days after exposure. It is one of three forms of plague, the other two being septicemic plague and bubonic plague.
Ehrlichiosis (; also known as canine rickettsiosis, canine hemorrhagic fever, canine typhus, tracker dog disease, and tropical canine pancytopenia is a tick-borne disease of dogs usually caused by the organism Ehrlichia canis. Ehrlichia canis is the pathogen of animals. Humans can become infected by E. canis and other species after tick exposure. German Shepherd Dogs are thought to be susceptible to a particularly severe form of the disease, other breeds generally have milder clinical signs. Cats can also be infected.
Tularemia, also known as rabbit fever, is an infectious disease caused by the bacterium Francisella tularensis. Symptoms may include fever, skin ulcers, and enlarged lymph nodes. Occasionally, a form that results in pneumonia or a throat infection may occur.
An animal bite is a wound, usually a puncture or laceration, caused by the teeth. An animal bite usually results in a break in the skin but also includes contusions from the excessive pressure on body tissue from the bite. The contusions can occur without a break in the skin. Bites can be provoked or unprovoked. Other bite attacks may be apparently unprovoked. Biting is a physical action not only describing an attack but it is a normal response in an animal as it eats, carries objects, softens and prepares food for its young, removes ectoparasites from its body surface, removes plant seeds attached to its fur or hair, scratching itself, and grooming other animals. Animal bites often result in serious infections and mortality. Animal bites not only include injuries from the teeth of reptiles, mammals, but fish, and amphibians. Arthropods can also bite and leave injuries.
Murine typhus is a form of typhus transmitted by fleas, usually on rats. Murine typhus is an under-recognized entity, as it is often confused with viral illnesses. Most people who are infected do not realize that they have been bitten by fleas.
Rat-bite fever is an acute, febrile human illness caused by bacteria transmitted by rodents, in most cases, which is passed from rodent to human by the rodent's urine or mucous secretions. Not to be confused with Rat fever which is usually alternative name for Leptospirosis. Alternative names for rat-bite fever include streptobacillary fever, streptobacillosis, spirillary fever, bogger, and epidemic arthritic erythema. It is a rare disease spread by infected rodents and can be caused by two specific types of bacteria. Most cases occur in Japan, but specific strains of the disease are present in the United States, Europe, Australia, and Africa. Some cases are diagnosed after patients were exposed to the urine or bodily secretions of an infected animal. These secretions can come from the mouth, nose, or eyes of the rodent. The majority of cases are due to the animal's bite. It can also be transmitted through food or water contaminated with rat feces or urine. Other animals can be infected with this disease, including weasels, gerbils, and squirrels. Household pets such as dogs or cats exposed to these animals can also carry the disease and infect humans. If a person is bitten by a rodent, it is important to quickly wash and cleanse the wound area thoroughly with antiseptic solution to reduce the risk of infection.
Yersiniosis is an infectious disease caused by a bacterium of the genus Yersinia. In the United States, most yersiniosis infections among humans are caused by Yersinia enterocolitica.
The Oriental rat flea, also known as the tropical rat flea, is a parasite of rodents, primarily of the genus Rattus, and is a primary vector for bubonic plague and murine typhus. This occurs when the flea has fed on an infected rodent and bites a human, although this flea can live on any warm blooded mammal.
The human flea – once also called the house flea – is a cosmopolitan flea species that has, in spite of the common name, a wide host spectrum. It is one of six species in the genus Pulex; the other five are all confined to the Nearctic and Neotropical regions. The species is thought to have originated in South America, where its original host may have been the guinea pig or peccary.
Theories of the Black Death are a variety of explanations that have been advanced to explain the nature and transmission of the Black Death (1347–51). A number of epidemiologists and since the 1980s have challenged the traditional view that the Black Death was caused by plague based on the type and spread of the disease. The confirmation in 2010 and 2011 that Yersinia pestis DNA was associated with a large number of plague sites has renewed focus on plague as the leading hypothesis, but has not yet led to a final resolution of all these questions.
Sylvatic plague is an infectious bacterial disease caused by the bacterium Yersinia pestis that primarily affects rodents such as prairie dogs. It is the same bacterium that causes bubonic and pneumonic plague in humans. Sylvatic, or sylvan, means 'occurring in wildlife,' and refers specifically to the form of plague in rural wildlife. Urban plague refers to the form in urban wildlife.
Urban plague is an infectious disease among rodent species that live in close association with humans in urban areas. It is caused by the bacterium Yersinia pestis which is the same bacterium that causes bubonic and pneumonic plague in humans. Plague was first introduced into the United States in 1900 by rat–infested steamships that had sailed from affected areas, mostly from Asia. Urban plague spread from urban rats to rural rodent species, especially among prairie dogs in the western United States.
Feline zoonosis are the viral, bacterial, fungal, protozoan, nematode and arthropod infections that can be transmitted to humans from the domesticated cat, Felis catus. Some of these are diseases are reemerging and newly emerging infections or infestations caused by zoonotic pathogens transmitted by cats. In some instances, the cat can display symptoms of infection and sometimes the cat remains asymptomatic. There can be serious illnesses and clinical manifestations in people who become infected. This is dependent on the immune status and age of the person. Those who live in close association with cats are more prone to these infections. But those that do not keep cats as pets are also able to acquire these infections because of the transmission can be from cat feces and the parasites that leave their bodies.
Madagascar has experienced two outbreaks of bubonic and pneumonic plague in the 21st century. In 2014, 40 died, and in 2017, 221 died.